Over the past several years, the television industry has seen a great amount of activity focused on enhancing the basic television-viewing platform. While declining in overall use due to emergence of alternatives for home leisure time, such as the Internet on home PCs and video gaming, home television systems still represent a large share of the entertainment/advertising market. Because of this status, an enhanced form of television has been sought by the television industry for at least the last 15 years.
Enhanced television involves components beyond standard audio/video programming delivered in a linear fashion. These components include but are not limited to pushed data files, interactive components and data streams. While such “Enhanced TV” components might typically be delivered as part of the television service, even in this case they are present as discrete elements in the multiplex (i.e., digital transport stream). Additionally, functionality is required at the receiver to extract these components, reassemble them and act accordingly.
One problem that the US TV broadcast industry faces is that only approximately 15% of television viewers receive their signals directly from broadcaster antennas. The remaining viewers receive their signals from another provider, such as cable, satellite and/or Telco (IPTV), i.e., a Multi-channel Video Programming Distributor (MVPD). Depending upon business arrangements, these distribution systems more often than not strip off components other than the linear television. Thus, for the approximately 85% non-antenna viewers, any enhanced components provided by the TV broadcaster would not be available. Additionally, for most of these viewers, a Set-Top Box (STB) is used for the reception/decoding of DTV signals, and the TV is used only as a viewing device. The STBs deployed by the MVPD will support any enhanced functions enabled by the MVPD themselves—generally not those from the broadcaster. In short, the various MPVDs have established a strong controlling position versus the local broadcasters for deployment of advanced forms of television content and associated revenues.
In a typical viewer arrangement, MPVD-deployed STBs tune/demux/decode the DTV signals and connect to the television using one of a number of means, such as via HDMI (High-Definition Multimedia Interface). This connection typically carries only decoded video/audio. In order to enable the reception and use of enhanced broadcast content by an increased number of TV viewers, mechanisms for delivering the enhancements directly to the television sets and coordinating the delivered elements with the linear programming, regardless of the delivery path, are desirable.